Types of Collagen: Which Ones Exist and What Each One Is Used For

Collagen is one of the most important proteins in the body and plays a fundamental role in the structure of the skin, bones, cartilage, tendons, and numerous connective tissues. However, many people are unaware that there is not just one type of collagen, but different types of collagen, each with specific functions within the body.

Knowing what the main types of collagen are, where they are found, and what each one is used for will help you understand which supplements may be most appropriate for your needs, whether it is to care for your skin, strengthen your joints, or maintain bone health.

What Is Collagen and What Is It Made Of?

What Is Collagen

Collagen is the most abundant structural protein in the human body. It accounts for approximately 30% of all proteins in the body and is part of virtually all connective tissues.

Its main function is to provide strength, elasticity, and support to structures such as the skin, cartilage, ligaments, tendons, bones, blood vessels, and the cornea. Thanks to collagen, these tissues maintain their firmness and can withstand daily stress.

As the years go by, the natural production of collagen decreases progressively. From the age of 25, a gradual decline begins, which can translate into the appearance of wrinkles, loss of skin elasticity, joint discomfort, or lower bone density.

How Collagen Is Formed in the Body

The body manufactures collagen naturally using different amino acids, mainly glycine, proline, and hydroxyproline. For this process to be carried out correctly, various nutrients that participate in its synthesis are also necessary.

Among them, vitamin C stands out in particular, as it is essential for forming stable and resistant collagen fibers. In addition, minerals such as zinc and copper, along with a balanced diet rich in protein, contribute to maintaining adequate production.

When synthesis decreases due to age, oxidative stress, smoking, a poor diet, or excessive sun exposure, tissues begin to lose some of their mechanical properties.

Why There Are Different Types of Collagen

Not all body tissues need the same characteristics. The skin requires elasticity and firmness, while cartilage must withstand constant impacts and bones need great structural strength.

For this reason, there are different types of collagen, each with a distinct composition and organization that allows it to adapt perfectly to the function it performs.

Although they all share a basic structure based on three protein chains intertwined to form a triple helix, the small variations between them make each type more suitable for a specific tissue.

How Many Types of Collagen Are There?

The 28 Known Types of Collagen

Currently, 28 different types of collagen have been identified in the human body. Each is given a Roman numeral (Type I, Type II, Type III, etc.) and has a specific function within the body.

Some participate in the formation of skin and bones, others are essential for cartilage, while certain types are involved in very specific tissues such as the cornea, kidneys, or basement membranes.

Although they all have biological importance, most account for a very small percentage of total body collagen and perform highly specialized functions.

What Are the Most Important Ones

Of all the existing types, the most abundant and relevant for health are:

• Type I Collagen: is the most abundant in the body and accounts for nearly 90% of body collagen. It is found mainly in the skin, bones, tendons, and ligaments.

• Type II Collagen: is found almost exclusively in articular cartilage and helps cushion impacts and promote joint movement.

• Type III Collagen: is present in the skin, muscles, blood vessels, and internal organs, providing elasticity and support to soft tissues.

• Type IV Collagen: is part of the basement membranes that surround different organs and tissues, playing a structural and filtration role.

• Type V Collagen: participates in the formation of the cornea, placenta, some cellular tissues, and certain Type I collagen fibers.

These five types concentrate much of the body's most important structural functions and are the most studied by the scientific community.

Which Types Are Used in Supplementation

In the field of supplementation, not all 28 types of collagen are used. The products available tend to focus on those that have the most evidence and are related to the most common needs of consumers.

The most used are:

• Type I Collagen: primarily aimed at the care of the skin, bones, tendons, and ligaments.

• Type II Collagen: used especially for the maintenance of cartilage and joints.

• Type III Collagen: is usually combined with Type I in supplements intended to improve the elasticity and firmness of the skin.

In addition to the type of collagen, it is also important to consider its form of presentation. Hydrolyzed collagen is one of the most widely used because its peptides have a smaller molecular size, which facilitates their digestion and absorption.

In the following sections, we will analyze in detail each of the main types of collagen, where they are found, what their functions are, and when it may be advisable to choose a specific supplement.

Type I Collagen

Type I collagen is the most abundant in the body and the most present in the human body. It is estimated to represent about 90% of total collagen, so it plays an essential role in the structure and strength of numerous tissues.

It is the best-known type of collagen and is usually associated with skin care, although its functions go much further.

Where It Is Found

Type I collagen is primarily present in tissues that require high tensile strength. It is found naturally in:

• Skin.

• Bones.

• Tendons.

• Ligaments.

• Teeth.

• Cornea.

• Part of the blood vessels.

Its structure is made up of very compact fibers that provide firmness and strength, allowing these tissues to withstand continuous stress without losing stability.

Due to its high presence in the skin, the natural decrease of this type of collagen is one of the main culprits for the appearance of wrinkles, loss of elasticity, and sagging associated with aging.

Functions of Type I Collagen

Type I collagen participates in numerous structural functions within the body. Among the most important are:

• Maintaining the firmness and elasticity of the skin.

• Providing strength to bones.

• Promoting the integrity of tendons and ligaments.

• Contributing to the good condition of teeth and gums.

• Participating in natural tissue repair processes.

In addition, it is part of the extracellular matrix, a structure that provides support to cells and helps maintain the architecture of different organs and tissues.

Thanks to these functions, Type I collagen is especially relevant for maintaining healthy-looking skin and a strong musculoskeletal system.

When to Choose a Type I Collagen Supplement

Type I collagen supplements are usually recommended when the main goal is related to skin health or the maintenance of tissues rich in this type of protein.

It can be an interesting option for people who wish to:

• Promote the elasticity and firmness of the skin.

• Maintain strong bones.

• Care for tendons and ligaments.

• Complement a diet aimed at healthy aging.

• Support natural collagen production after a certain age.

It is usually marketed as hydrolyzed collagen, as its peptides have high bioavailability and are easy to incorporate into the daily diet.

Type II Collagen

Type II collagen is the main structural component of cartilage and is an essential protein for the proper functioning of the joints.

Unlike Type I collagen, which predominates in the skin and bones, this type is specialized in providing flexibility and shock-absorbing capacity to joint surfaces.

For this reason, it is one of the types of collagen most used in supplements aimed at joint care.

Where It Is Found

Type II collagen is located almost exclusively in hyaline cartilage, a tissue that covers the joint surfaces and facilitates movement between bones.

It is also present in:

• Knees.

• Hips.

• Shoulders.

• Ankles.

• Wrists.

• Ribs.

• Nasal septum.

• Some ear structures.

Its organization allows it to absorb impacts and distribute the loads supported by the joints during activities such as walking, running, or climbing stairs.

Over time, natural wear and tear of cartilage can reduce the amount and quality of Type II collagen present in the joints.

Functions of Type II Collagen

The main functions of Type II collagen are related to the protection and proper functioning of cartilage.

Among them are:

• Maintaining the structure of articular cartilage.

• Promoting shock absorption between bones.

• Contributing to joint mobility.

• Helping distribute mechanical loads during movement.

• Participating in the maintenance of cartilaginous tissue.

Thanks to these properties, cartilage retains its elasticity and can withstand thousands of daily movements by reducing friction between joint surfaces.

When to Choose a Type II Collagen Supplement

Type II collagen supplements are usually aimed at people who want to care for their joints or maintain cartilage in good condition.

They can be especially interesting for:

• People with high physical activity.

• Athletes who subject their joints to repetitive impacts.

• Older adults.

• Those who wish to maintain joint mobility over the years.

• People looking to complement a routine focused on joint health.

Depending on the product, Type II collagen can be found in hydrolyzed form or as undenatured Type II collagen (UC-II®), two formats with different characteristics that we will analyze later in the article.

Type III Collagen

Type III collagen is the second most abundant type of collagen in the body and is usually found alongside Type I collagen in numerous tissues. Its main characteristic is to provide elasticity and flexibility to structures that need to withstand continuous movement without losing their shape.

For this reason, it plays an especially important role in the skin, blood vessels, and various internal organs.

Where It Is Found

Type III collagen is mainly present in soft tissues that require a combination of strength and elasticity. It is naturally located in:

• The skin.

• Blood vessels.

• Muscles.

• Intestinal walls.

• The uterus.

• The lungs.

• Various internal organs.

Its presence also increases during the early stages of healing, as it participates in the formation of new tissue before it matures and is progressively replaced by Type I collagen.

Its distribution explains why this type of collagen is so important for maintaining the elasticity of numerous tissues in the body.

Functions of Type III Collagen

The main functions of Type III collagen are related to the support and flexibility of soft tissues.

Its standout functions include:

• Maintaining skin elasticity.

• Providing structural support to internal organs.

• Promoting blood vessel resistance.

• Participating in natural repair and healing processes.

• Contributing to the maintenance of muscle tissue.

Its work in conjunction with Type I collagen allows the skin to maintain a balance between firmness and elasticity, two fundamental characteristics for maintaining a healthy appearance.

When to Choose a Type III Collagen Supplement

Type III collagen is rarely marketed in isolation. It is most common to find it combined with Type I collagen, as both appear together naturally in numerous tissues.

Supplements containing these two types of collagen are usually aimed at people who are looking to:

• Promote skin elasticity and firmness.

• Maintain the good condition of connective tissues.

• Complement an anti-aging skincare routine.

• Support the maintenance of tendons and ligaments.

• Support natural collagen production over the years.

This combination is one of the most widely used in supplements intended for the comprehensive care of the skin and the musculoskeletal system.

Other Types of Collagen

Although types I, II, and III are the best known and most used in supplementation, there are many other types of collagen that play essential roles within the body.

Most are present in very specific tissues and perform highly specialized tasks, which is why they tend to receive less attention outside of the scientific field.

Type IV Collagen

Type IV collagen is part of the so-called basement membranes, thin layers that serve as support for different cells and tissues in the body.

It is mainly found in:

• The skin.

• The kidneys.

• The lungs.

• The lens of the eye.

• Blood vessels.

• Various internal organs.

Unlike other types of collagen, Type IV does not form long, resistant fibers. Instead, it creates a type of network that provides stability, facilitates the filtration of substances, and helps separate different tissues.

Its function is essential for the proper functioning of numerous organs.

Type V Collagen

Type V collagen appears in much smaller quantities than the previous ones, but plays a very important role in the organization of other collagen fibers.

It can be found in:

• The cornea.

• The placenta.

• Hair.

• Some cellular tissues.

• Fetal membranes.

In addition to being part of these tissues, it participates in the regulation of the size and arrangement of Type I collagen fibers, contributing to tissues maintaining an appropriate structure.

Although it is barely mentioned in nutritional supplements, it is an essential protein for the proper development of different body structures.

Why There Are More Than 20 Types of Collagen

Each tissue in the body needs different mechanical properties. While bones require great strength, cartilage must absorb shocks, and blood vessels need to combine firmness with flexibility.

To respond to these needs, nature has developed 28 types of collagen with slightly different structures and highly specialized functions.

Some form very strong fibers capable of withstanding high tension, while others create support networks or participate in the organization of other extracellular matrix proteins.

Although all are important for the functioning of the body, types I, II, and III account for most of the body's collagen and are the ones that are of greatest interest from a nutrition and supplementation standpoint, which is why they are the stars of most scientific studies and supplements available on the market.

Which Type of Collagen to Choose Based on Your Goal?

There is no single type of collagen that is best for everyone. The choice will mainly depend on the goal you are pursuing, as each type of collagen is present in different tissues and performs specific functions.

Knowing these differences allows you to select a supplement more adapted to each person's needs and make better use of their characteristics.

For the Skin

If the goal is to maintain firm, elastic skin with a good appearance, the most commonly used supplements are those that contain Type I collagen, usually combined with Type III collagen.

This combination is found naturally in the skin and participates in maintaining its structure, elasticity, and resistance.

In addition, many supplements intended for skincare incorporate vitamin C, an essential nutrient for normal collagen synthesis.

They are usually an option chosen by people who want to care for their skin against the passage of time or complement a facial care routine from within.

For Joints

When the main goal is joint care, the star is usually Type II collagen, as it constitutes the most important structural component of cartilage.

These types of supplements are aimed at people who want to maintain joint mobility or help protect cartilage against wear and tear associated with physical activity or aging.

Depending on the product, it can be found in the form of hydrolyzed collagen or undenatured Type II collagen (UC-II®), two formats with different characteristics.

For Bones and Connective Tissues

Bones, tendons, and ligaments mainly contain Type I collagen, which is why this is usually the type most used when the goal is related to the maintenance of these tissues.

It is also common to find supplements that combine Type I and Type III collagen to offer more comprehensive support to all connective tissues.

In some cases, these products incorporate minerals such as magnesium or vitamins that participate in the normal maintenance of bones.

For General Use

If looking for a general-use supplement, it is most common to opt for Type I and III hydrolyzed collagen, as they are the most abundant types in the body and participate in numerous tissues.

These types of products are usually used as a supplement within a balanced diet and a healthy lifestyle.

However, if the main goal is the joints, it is usually more appropriate to consider a specific supplement that includes Type II collagen.

How to Choose a Collagen Supplement

There is currently a wide variety of collagen supplements on the market. Although many products share similar ingredients, there are several aspects that should be reviewed before choosing one.

Knowing these differences will help you select a supplement that best adapts to your needs.

Type of Collagen

The first aspect you should check is the type of collagen the supplement contains.

• Type I: indicated mainly for skin, bones, tendons, and ligaments.

• Type II: aimed at the maintenance of cartilage and joints.

• Type III: normally appears combined with Type I to support the health of skin and connective tissues.

Some supplements mix several types of collagen to offer a broader approach, while others focus on a specific goal.

Source of Collagen

The source of the collagen can also vary between products.

The most common are:

• Marine collagen, obtained mainly from fish skin and scales, rich in Type I collagen.

• Bovine collagen, from cattle and commonly used for its Type I and III collagen content.

• Porcine collagen, used in some supplements for its composition similar to human collagen.

• Chicken collagen, used especially in products containing Type II collagen intended for joint care.

Each source has its own characteristics, although the choice will depend both on the goal sought and on personal preferences and possible dietary restrictions.

Supplement Format

Collagen can be marketed in different formats, each with its own advantages.

The most common are:

• Powder to dissolve in water, coffee, or smoothies.

• Capsules.

• Tablets.

• Single-dose sachets.

• Ready-to-drink beverages.

From a practical point of view, the format does not determine the effectiveness of the supplement. The most important thing is to choose one that is comfortable to take consistently, as regularity is often a key factor in any supplementation routine.

Ingredients Accompanying the Collagen

Many supplements incorporate other ingredients with the aim of complementing their formulation.

Among the most frequent are:

• Vitamin C, which contributes to normal collagen formation for the functioning of the skin, bones, and cartilage.

• Hyaluronic acid, present naturally in the skin and joints.

• Magnesium, related to the normal functioning of muscles and bones.

• Zinc, which contributes to the maintenance of skin, hair, and nails in normal conditions.

• Biotin, widely used in supplements intended for skin and hair care.

Choosing a supplement that combines the right type of collagen with complementary ingredients can help better tailor the product to your specific goals and needs.